The relates to a continuously variable transmission device of the type having driving and driven pulleys on different shafts, and in particular to a continuously variable transmission in which the spacing between V-belt grooves of the driving and driven pulleys is modulated, thereby changing the radius of the belt at the driving pulley or driven pulley to change the transmission speed ratio between the driving pulley and the driven pulley, the spacing modulation being driven by one or more than one kind of axial driving force, as follows:
1. by using a variable centrifugal force generation mechanism to change the rotational speed of the input shaft and generate a variable axial driving force that changes the spacing of the transmission V-belt grooves of the driving pulley;
2. by using a variable centrifugal force generating mechanism to change the rotational speed of the output shaft and generate a variable axial driving force that changes the spacing of the transmission V-belt grooves of the driven pulley;
3. by using a variable axial driving force generating mechanism to change the output shaft torque and generate a variable axial driving force that changes the spacing of the transmission V-belt grooves of the driving pulley;
4. by using a variable axial driving force generating mechanism to change the output shaft torque and generate a variable axial driving force that changes the spacing of the transmission V-belt grooves of the driven pulley; and/or
5. by providing the driving or driven pulley with an axial pre-pressed spring and pulling the driving or driven pulley using a belt type transmission component to generate an axial driving force that changes the variable spacing of the transmission V-belt grooves of both or either of the driving or driving pulley.
The above five methods of varying the groove spacing in a continuously variable transmission involve passive operations. Alternatively, the groove spacing may be actively varied by a linear driving force that is generated manually, or by mechanical power, electromagnetic effect, a hydraulically or pneumatically driven linear driving device; or revolving kinetic energy generated by an electric motor, hydraulic motor or pneumatic motor, and that is converted through a mechanical transmission device into an axial linear type driving force to change the spacing of the variable spacing transmission V-belt grooves of both or either of the driving pulley or driven pulley.
Such a continuously variable transmission device may have numerous different input and output shaft structures, including: rubber belt type, metal belt type, chain type, electronic (ECVT) type, and friction disk type.